Compared to stock it now has much better low RPM torque and pulls hard all the way to red line.
When I did the mods I had changed the muffler, did the re-jet, added a TwinAir filter, removed the snorkle and put on a 13 tooth sprocket all at the same time. Therefore my improved performance was as a result of all these changes. Made a big difference IMO.

 

wasn't there a post around here showing the difference in the needles? I was wondering which kit to get for my 09' SF and thought and seen a post a while back but can't find it now?????

 

Whats the mpg difference with all that?
Did your top speed go down due to the 13 tooth sprocket? But has faster acceleration?

 

Hi, I just got my 2009 KLX250S and I believe that the only performance mod is the aftermarket FMF Q4 muffler the previous owner added. He said he noticed a big difference right away. So now its time to re-jet, I've done lots of reading on this site, but am still unsure...

>>> what is the best kit for me for a 2009 bike, at this elevation? The Dynojet #2206 for the KLX300 sounds ok but requires drilling the slide, while the DJ kit for the 09/10 KLX250S doesn't. You can see it here: http://www.jcmotors.com/p-15337-dyno...250s-2009.aspx

>>> Also, is an aftermarket header really worth it when it is going to cost about $200? I hear the that the FMF Powerbomb is a reasonable choice and the website claims 10 percent power increase. How likely is that?

>>> I am planning on taking off the snorkel and drilling out the hole to 3x3, or maybe putting on the higher flowing KDX 200 snorkel (I do some deeper stream crossings).

>>> I was planning on removing the smog stuff, but the page which shows you how to do it says that there are no performance benefits, it just "cleans up the area under the tank". So, I probably won't bother. http://klxforum.suncup.net/viewtopic...t=smog+removal

I appreciate your input,
Luke

 

Hey lukeorion, you dont HAVE to drill the slide with any kit. The kit that I got said to drill it and even came with the drill bit but I didnt drill it and I still have a huge difference in performance. The major gains are going to come from the jetting difference although I would like to know how much more difference you can get from drilling the slide.

 

If you don't want to drill the slide (WHY!) then just cut 2 turns out of the stock spring and you'll have a similar effect, or you can wire two turns together with lockwire to shorten the spring.
Here'a pic' for those that wonder!


And another.

 

[QUOTE=WestOzKLX;417209]If you don't want to drill the slide (WHY!) then just cut 2 turns out of the stock spring and you'll have a similar effect, or you can wire two turns together with lockwire to shorten the spring.
Here'a pic' for those that wonder!



[IMG][/IMG]

IS THIS RIGHT?

 

09KLX, look at the tips of the needles and their tapper....that is the difference.

 

Since the 300 needle gets really skinny really fast it would act to richen up the lower throttle settings right? Basicly, the 300 dumps fuel off idle to get snappy response? Sounds like a pseudo accelerator pump. The taper rate after the crazy low end looks similar between the two needles.

 

Is the image I modified right for the left needle?